In the persons contact list have the "File As" field for their contacts changed to "Last, First" and it will sort by last name. However if you want GAL results to be "Last, First" I don't know how that can be done...

well yes this is part of the solution, thanks, but i mean in the whole zimbra, it is when you look for someone on GAL by the To or CC button, or when make search on GAL or on internal LDAP, i mean all the functionalities where you have names should be sorted like it, last name, and first name any idea?

The same question - can I have GAL sorted by last name? I mean in "CC" and "To" fields when I compose new emails, in "From" field when I send email outside zimbra server (now is displayed Firstname Lastname <address@domain.tld>).